The warning comes in the wake of a series of sea lion encounters, the latest being at Smaills Beach on Wednesday evening.
Senior Sergeant Anthony Bond, of Dunedin, said police went to Tomahawk Rd, Ocean Grove, after reports of people trying to move a pregnant sea lion off the middle of the road at 9.10pm.
The sea lion, believed to be well-known local Gem, was moving along the road to a nesting area.
"She has been moving at a rate of about 20m every 10 minutes — so going very slowly," Snr Sgt Bond said.
Doc coastal biodiversity Otago ranger Jim Fyfe, who notified police of Gem’s whereabouts, said she was first seen on the hill above Smaills Beach.
"We were wondering whether she was going to nest in there to have a pup," Mr Fyfe said.
"She obviously decided it wasn’t the spot for her and got up and started using [the road]."
The incident was more of a traffic management issue than a conservation one, so he rang the council and police for aid, Mr Fyfe said.
It was not uncommon for sea lions to come kilometres inland and to high elevations to nest, he said.
"People using coastal roads really need to be aware that this is going to happen at this time of year in the breeding season.
"We can’t predict everywhere that a sea lion might come up, but certainly the Tomahawk and Smaills area is being well used by the breeding female sea lions at the moment."
Even sea lions with regular nesting patterns could stray into traffic.
A female sea lion, named Hiriwa, who had regularly birthed pups on Chisholm Links for the past four years, had strayed further than her usual choice of nesting place to Tahuna Rd.
‘‘By the time we saw her . . . she was tuckered out and trying to sleep in somebody’s backyard,’’ Mr Fyfe said.
‘‘It is another good example of how these pregnant females are trying to fine secure place which brings them inland and the roads are the issue.’’
A male sea lion, named Huna, was killed after it was hit by a car on Southdale Road, on Boxing Day last year.
